The experiment used mice whose brain cells had been genetically engineered to glow yellow when storing memories and red when recalling them.

In a memory test involving a lemon scent and electric shocks, mice with Alzheimer's disease were unable to recall the a link between the smell and getting shocked. This reaction was mirrored in their brain cells: while red and yellow neurons appeared to overlap in healthy mice, the wrong cells glowed red in the mice with Alzheimer's, suggesting they were calling up incorrect memories.

The team believe this could explain why Alzheimer's disease can often cause sufferers to remember false memories.

However, by stimulating their neurons with a laser, the team were able to activate the ill mice's memory-storing brain cells, prompting them to recall the association between the lemon scent and being shocked.

Scientists now believe this shows that "lost" memories could be recovered.

They hope the discovery could lead to further research, and the creation of drugs that could help reactivate memories in Alzheimer's sufferers.

Newsletter Signup

Don't miss out on Prima direct to your inbox

Please tick here if you would prefer not to receive the latest special offers, promotions and product information from Hearst Magazines UK.
Tick here if you would like to receive special offers and really useful information from our approved partner companies. You won't get bombarded and you'll be able to unsubscribe at any time.